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To: Jonathan Morton <chromatix99@gmail.com>, Pete Heist <pete@heistp.net>
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Date: Wed, 22 Aug 2018 12:13:29 +0200
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Subject: Re: [Cake] issue with Cake and bpf filter
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Jonathan Morton <chromatix99@gmail.com> writes:

>> On 22 Aug, 2018, at 12:51 pm, Pete Heist <pete@heistp.net> wrote:
>> 
>> "math between pkt pointer and 4294901760 is not allowed"
>
> As a possible clue here, 4294901760 == (2^32) - (2^16).
>
> I suspect both errors are being caused by the call to memcpy(). This
> potentially inlines a substantial amount of code which may not be
> eBPF-clean.

Yeah, I think this is a good guess. You could try using
__builtin_memcpy() instead; that may do fewer pointer shenanigans than
the function-header-defined one...

-Toke